What Are Pheromones? Do Humans Have Pheromones?

A pheromone is a chemical an animal produces which changes the behavior of another animal of the same species (animals include insects).

Some describe pheromones as behavior-altering agents. Many people do not know that pheromones trigger other behaviors in the animal of the same species, apart from sexual behavior.

Pheromones, unlike most other hormones are ectohormones - they act outside the body of the individual that is secreting them - they impact a behavior on another individual. Hormones usually only affect the individual that is secreting them.

This article will take a brief look at pheromones and whether they can be found in humans.

Fast facts on pheromones

Here are some key points about pheromones. More detail and supporting information is in the main article.

Pheromones are similar to hormones but work outside of the body

Pheromones induce activity in other individuals, such as sexual arousal

Some chemicals have been investigated for pheromone actions in humans but evidence is weak

Virtually all insects use pheromones to communicate

Most alleged pheromone products that can be purchased online are ineffective

Gustav Jäger was the first to propose the idea of pheromones - he called them anthropines

There are four types of pheromone: releaser, primer, signaler and modulator.

What do pheromones do?

Pheromones are widely utilized throughout the animal population.

Pheromones can be secreted to trigger many types of behaviors, including:

Alarm

To follow a food trail

Sexual arousal

To tell other female insects to lay their eggs elsewhere (epideictic pheromones)

To respect a territory

To bond (mother-baby)

To back off.

It is believed that the first pheromone was identified in 1953. Bombykol is secreted by female moths and is designed to attract males. The pheromone signal can travel enormous distances, even at low concentrations.

Experts say that the pheromone system of insects is much easier to understand than that of mammals, which do not have simple stereotyped insect behavior.

It is believed that mammals detect pheromones through an organ in the nose called the VNO (Vomeronasal Organ), or Jacobson's organ, and connects to the hypothalamus in the brain.

The VNO in humans consists of just pits that probably do not do anything; interestingly the VNO is clearly present in the fetus but atrophies before birth. If humans do respond to hormones, most likely they use their normal olfactory system.

Pheromones are commonly used in insect control. They can be used as bait to attract males into a trap, prevent them from mating, or to disorient them.

Do humans have pheromones?

According to thousands of websites that promise sexual conquests if you buy their pills, human pheromones exist - bear in mind that their aim is to get you to buy their products. However, most proper, well-controlled scientific studies have failed to show any compelling evidence.

Some believe that androstenone acts as a human pheromone.

Gustav Jäger (1832-1917), a German doctor and hygienist is thought to be the first scientist to put forward the idea of human pheromones. He called them anthropines and said that they were lipophilic compounds associated with skin and follicles that mark the individual signature of human odors. Lipophilic compounds are those that tend to combine with, or are capable of dissolving in lipids.

Researchers at the University of Chicago claimed that they managed to link the synchronization of women's menstrual cycles to unconscious odor cues. The head researcher was called Martha McClintock, hence the coined term "the McClintock effect."

When exposing a group of women to a whiff of sweat from other women, their menstrual cycles either accelerated or slowed down, depending on when during the menstrual cycle the sweat was collected - before, during or after ovulation.

The scientists said that the pheromone collected before ovulation shortened the ovarian cycle, while the pheromone collected during ovulation lengthened it. Even so, recent analyses of McClintock's study and methodology have questioned its validity.

Recent research into pheromones

A Swedish study found that lesbians react differently to AND (progesterone derivative 4,16-androstadien-3-one) compared with heterosexual women. AND is ten times more abundant in human male sweat than female sweat.

A study, published in Respirology in January 2016, showed that AND caused swelling in the erectile tissue of female noses. This was taken as evidence that AND might be a functioning pheromone.1

Another contender for the role of human pheromone is androstadienone. There is some evidence that androstadienone, a component of male sweat, increases attraction, affects mood and cortisol levels and activates brain areas linked to social cognition. One study found that androstadienone increased cooperative behavior in males.2

Androstenone, secreted only by males, has also been tested for its potential role as a pheromone. According to some studies, androstenone increases a woman's mood, especially if she is presented with it close to the time of ovulation.3

Overall, evidence for the existence of pheromones in humans is weak but it can not be ruled out entirely. If human pheromones are ever found, the likelihood is that their effects are incredibly subtle.

Types of pheromone

There are four principal kinds of pheromones:

Releaser pheromones - they elicit an immediate response, the response is rapid and reliable. They are usually linked to sexual attraction.

Primer pheromones - these take longer to get a response. They can, for example, influence the development or reproduction physiology, including menstrual cycles in females, puberty, and the success or failure of pregnancy. They can alter hormone levels. In some mammals, scientists found that females who had become pregnant and were exposed to primer pheromones from another male, could spontaneously abort the fetus.

Signaler pheromones - these provide information. They may help the mother to recognize her newborn by scent (fathers cannot usually do this). Signaler pheromones give out our genetic odor print.

Modulator pheromones - they can either alter or synchronize bodily functions. Usually found in sweat. In animal experiments, scientists found that when placed on the upper lip of females, they became less tense and more relaxed. Modulator hormones may also affect a female's monthly cycle.

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at 11 yeas old i fell in love with a boy that i slept with (no sex) and have spent 35 years wanting and needing to be with. I have written a book and tried many times to explain the way he smelled. i have over the years visited him to try to let him go and each time it got worse. i smelled another man at one point that smelled like him and was intantly returened to painfully wanting and needing him. upon realizing recently that I have been keeping a wealthy, intelligent man away from me because i don't like the way he smells i realized that i have suffered for 35 years from pheromone withdraw. I know they exist!

When I was 32 years old I was hanging out with an acquaintance at a naughty club. She disrobed and got all the men gawking at her, nut I wasn't interested. Then, a guy she knew started walking toward her from afar and he body gave off an increasingly intense musky scent so attractive to he that he rushed toward her and so unappealing to me that I rushed out of the club to gain some relief. I spoke with other guys I knew, some who said they thought her scent was irresistible and others who said they thought her scent was awful. Was this a pheromone bombardment to attract compatible males and scare away pheromonically incompatible males away?

When I was 42 years old and in nursing school I walked without paying attention into the room of a woman who has recently given birth. Before seeing her I was bombarded with an intense scent which confused me at first and then left me desiring her not knowing why, and unable to shake the feeling? Was this the result of a pheromone bombardment?

I came across this pheromone an ectohormone which not only found as an attractant in insects but in mammals and humans too, in a documentary I watched, now according to this documentary it helps detect the right choice of partner by producing an attraction between two compactible DNA's....a complicated chemistry I must say.so I like to know more about the role of pheromones and DNA paring. Thanks.

Not having sex for 7 years, I met a fellow, we bonded instantly, dated, the desire strong, After he went back to Ontario, thoughts of him while I was in the middle of a store or restaurant...my pheromone odour became very strong. I could smell it.

Even younger fellows glanced at me more often, or a fellow standing in line close to me. I embrace the feeling that even at 67 years old, one can still release pheromones!

I know there has to be something affecting other people that is beyond my control... I've had many problems with unwanted attention from females (I'm married), most men don't like me, and I'm not that good looking either.

I've had friendships I've had to break off so they did not interfere with my marriage (still have a perfect record), and have even been dropped by female doctors, one of which admitted that her husband had a problem with me being her patient. Had three incidents today, all of which I ignored or played off as usual.

So, that leads me to believe there is something going on, and it gets worse on the days after I have relations with my wife. I almost never sweat either, so AND affecting things does not seem likely to me. Oh well, perhaps someday we'll learn more.

I have walked into a room full of women that don't seem to have any kind of attraction to me, and I can go sit in the back away from everyone, and if I even make myself slightly aroused i find all of the women within about 20 ft of me having trouble sitting still, laughing at everything, and having trouble looking away from me.

Keep in mind i am not even all that attractive looking, and i am introverted mostly, so, i strongly believe either this is electromagnetic or pheromones.

I've read an article of selling a product that can produced phermones if we use it. It said that things can be used to attract girl who we like.. not only that, other female will attracted to us too when we used the product. then, when i want to get more information about the phermones and VNO, i found that it was produce by mammals ANIMALS. After that, I only can said "OMG". So, I'm confused now. The products was made by pheromones of animals or what?? I still wonder about it..

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